shmish

Hi,

I'm going to rebuild my rear Alfine wheel to replace a broken rim. Since I'll have the hub off, is there any (preventative) maintenance I should do on it? I don't have any big issues as far as I know. The wheel does skip now and then which is very annoying and slightly dangerous. I have the yellow lines aligned so I'm not sure if there is anything else I can do about it. I have somewhere between 6000 and 8000 km on the hub I think.

thanks

sweeks

Check this site and see what you find: https://hubstripping.wordpress.com/alfine-shimano/

IIRC, the 8-speed Alfine is similar to the 8-speed Nexus. It wouldn't hurt to dip the internals in gear oil (some use ATF; I use gear oil on 2 Nexus hubs and my Alfine 11) and re-lube the bearings with grease. This can be done without disassembly of the gear cluster.
Steve

shmish

Thanks for the link and the reply.
Reading up on it, it seems some people have good success with oil immersion with the 8spd while others find that the seals leak a bit with oil. I wonder what the alternative is, if I don't do an oil immersion? I don't want to disassemble the whole thing.

sweeks

I think the only good alternative to the "dip" is grease, which pretty much requires disassembly. The gears are in sub-assemblies that aren't too difficult to get off the cluster or put back. The sub-units only need disassembly for a really thorough cleaning and (IMO) can be left intact for re-greasing.

The oil dip is much easier. I have found that gear oil (I use Royal Purple 75W-140, which has similar properties to the Shimano Alfine oil and is 20-25% of the cost) has less of a tendency to run off than ATF. After the dip, I let the cluster drip for a half hour before reinstallation in the hub. Even though my Nexus hubs have relatively poor seals, I have not had a significant leakage problem.

I pack the bearings with the regular Nexus grease, which theoretically helps with keeping the oil inside the hub.

Speaking of Nexus grease, when I started looking inside Nexus hubs, the "official" grease was a black paste which looks like it contains molybdenum disulfide. My first Nexus 8-speed hub used the same grease, seemingly. My second N-8, a "red band", had a white grease, like lithium grease. I use the black stuff on all these hubs, partly because I bought two tubes of it and partly because the black stuff is easier to clean off the parts.

If you haven't seen Aaron's Bicycle Repair, they have some good pictures: Internal Gear Hub Service.
Steve

EDIT: More on this thread: https://www.bikeforums.net/bicycle-me...nexus-igh.html

wschruba

The white grease is slightly runnier than the moly grease, which Shimano now specifies for their coaster brake hubs. It also mixes readily with the nexus oil, which I suspect is the bigger plus to it; after servicing one, riding around the block, and opening it up to satisfy my curiosity, the internals were a pretty uniform blue-ish white, with no distinguishable grease or oil, just the amalgam of the two.

BTW, if you are going to strip the hub down to the axle, it is easiest to clean the parts with diesel fuel, as you don't need to strip it off when you are done cleaning...which is prohibitively difficult, if you don't have all the tools to re-assemble the internal assembly.

sweeks

I use kerosene, which is pretty much the same as #1 diesel fuel - or that's what they told me when I worked on the railroad 50 years ago! It pretty much dries off, and what's left is a lubricant in its own right.
Steve

shmish

The disassembly requires one or two Shimano cone removal tools, correct?

sweeks

See Dan Burkart's instructional video here: https://www.bikeforums.net/19692927-post9.html

IIRC, the drive-side seal requires a large pliers or a purpose-made tool. The locknut and cone are removed with standard bike tools.
Steve

wschruba

In order to open the driver, a special drift is required that punches the driver body off the cone. A separate drift is used to reinstall the cone properly. Theoretically, you could do without this tools, but you'd have no idea if you put it together properly, and it is considered a critical dimension (ie, the hub won't work properly if you get it wrong).

sweeks

Well, this is where i admit that I have no experience with open-hub maintenance on Alfine hubs. My 8-speed hubs are Nexus; I have been under the impression that maintenance procedures on Alfine and Nexus hubs (8-speeds anyway) were similar.

Having said that, I don't recall seeing anything in Dan's video about these drifts, and I went to the Shimano "Tech Docs" site and couldn't find this information there either. Do you have a link to something about this? (I'm just curious... no Alfine purchases in my foreseeable future!)

So... I guess I'd advise the OP to proceed with caution and look for as much (authoritative) help as you can find!
Steve

wschruba

You can see the tools referenced in the upper right corner at https://si.shimano.com/#/en/EV/SG-S501-2788C

Basically, you remove the internal assembly, remove the e-clip from the left side, and pull the planetaries.

Remove the RH locknut, and place the split drift over the axle (how, will be obvious, when you see the tool and assembly in your hands). Cradling the axle assembly in one hand/carefully supported over the open throat of a vise, drive the drift down, popping the axle free.

At this point, the assembly will spring open, allowing you to remove the driver/access the RH wheel bearing.

After aligning the parts, you place the cone in the proper orientation, and use the installation drift to put the cone in at the proper depth. Install the locknut, and assemble the rest of the internals as normal. It is extremely important to make careful note of the orientation of every part, as almost none are bi-directional.

Shimano publishes a service manual for the above procedure, but it is only available to dealers. You might try calling them, but I wouldn't count on then making it available to you.

I also would not undertake the above without also buying new RH axle seals, as these are typically damaged by removal.

sweeks

Thanks! Now I'm *really* happy my hubs are Nexus! They're a snap to overhaul compared to the Alfine it would seem.

Of course, the Alfine-11 is even easier: nothing but oil changes!

I just watched Dan's video again... there were no drifts or special tools used. I think the drifts are needed for a level of disassembly above and beyond what it takes to simply lubricate the hub. I learned the hard way not to take the axle unit apart on a 7-speed Nexus hub... it's still my "rainy day challenge" project.
Steve

wschruba

I, also, find that the A11 is the easiest of all. I had initially opened my hub to grease the outside bearings, but upon my last total teardown, discovered that the grease had been displaced, and a fine film of oil was coating all the bearings (even those farthest from the hub shell's center, in the driver assembly). It would seem that grease is entirely unnecessary for the A11, in any capacity.

Aside from the peculiarity with the pressed on RH cone, the overhaul procedure is quite similar between the Nexus/Alfine family.

Dan Burkhart 

I think that was dealt with on this one.

sweeks

Thanks, Dan! That's more disassembly than I plan to get involved with. Dipping the gear cluster (Nexus; no disassembly) and greasing the bearings seems to work very well.

Off topic, I enjoyed some of your other videos documenting overhaul of some dynohubs. About 6 years ago, I submitted a protocol for servicing the Dahon Joule (early model) to Hubstripping. It was pretty basic; I like your video documentation better. (https://hubstripping.wordpress.com/2...le-dynamo-hub/)
Cheers,
Steve

Dan Burkhart 

Thanks for the link. I can't review it thoroughly right now as I'm vacationing with very limited internet access.
I will go through it when I can, it looks very interesting.

shmish

I have a tub of green Park Polylube 1000. Any ideas on whether or not this grease would be ok? I don't plan on doing an oil bath since my hub won't seal oil in.

I finally got the hub apart and it looks to be in great condition. There is still quite a bit of white grease inside.

Dan Burkhart 

The park grease is too stiff. It can and will interfere with the engagement of the roller clutches.
Shimano's special Nexus grease is the best stuff to use unless you switch to oil bath lube.

shmish

Thanks Dan. Your videos have been helpful too, BTW. I wonder if I can get the grease locally in Vancouver.

So for the oil dip: dip in gear oil or maybe ATF, or Shimano oil if you're rich. Let drip. Grease gears with shimano grease. Maybe put some Phil's Tenacious Oil (pictures of that on Aaron's Bicycle Repair and mention on sheldonbrown.com), and use marine grease for the outer bearings (I think my Park polylube would be good for the outer bearings too).

Dan Burkhart 

I've done the ATF dip on several hubs both Shimano and Sturmey Archer, and apart from sometimes being a bit messy, in every case hub performance was enhanced.
However, for my current commuter bike, equipped with an Alfine 501 series, I chose to stick with the Nexus grease.
I did apply the grease to some of the deep down parts that didn't seem to get much from the factory.
Greasing the moving parts in the shift spring assembly as well as the pawls and actuation arm definitely improves the function.
If you go the oil route, I suggest keeping the recipe simple. Use one type of oil exclusively to avoid the possibility of non compatible additives, and use grease on the outer bearings.

shmish

Maybe once every hour or two of riding I'll have my alfine "skip" while pedaling. The common remedy for this seems to be to check the alignment of the yellow dots on the hub. Mine are very well lined up, and I've also played with moving them around a bit, but this hasn't solved this problem. I wonder if this skipping is at all related to lubrication of the gears?

sweeks

I have the same thing with my Alfine 11. It happens about once every couple weeks or less, so it's nothing more than an annoyance. The gear alignment marks are always correctly aligned. I have a feeling it may be more likely due to friction in the shifter cable. If there is borderline resistance to motion in the shifter cable, it's likely to be noticed first in shifts powered by the hub's return spring (up-shifts in the Alfine 11). I have been lubricating the cable with Tri-Flow once a year with a pressure injector (see image) and the missed shifts are infrequent.
Steve

Reynolds 

I drilled and tapped my Nexus 8 for an oil port and use 15 ml ATF, changed about every 5000kms/1 year. 30000kms so far, not a problem, no skipping, no play, so I can't be sure ATF is the best, but certainly it doesn't do any harm.

sweeks

I eventually settled on a synthetic gear oil for my Nexus 11 (Max Gear Synthetic Gear Oil for Max Protection | Royal Purple). This was based on similar viscosity to the "official" but very expensive Shimano oil and a much lower price. I use 75W-140 because that was the only weight carried by the auto parts store in my area. It's basically just a 75W oil because it never gets anywhere near as hot as it would in an automotive application. After about 4,500 miles the hub still performs perfectly; there are very small metallic bits in the oil after it has been used, but very few compared to what was in the original OEM oil (which I replaced once). Interestingly, even though the oil does not get hot, the purple color goes away after 600 miles or so.

To your question: I was using ATF on my Nexus hubs, plus Nexus grease on the bearings, but I would get a little leakage if the bike was stored drive-side down. I switched to the RP gear oil because it is more viscous. After about a 10-minute draining period I reinstall the gear cluster, and I have not had any oil leaks. Because the oil is moderately expensive (~ $25/liter) I use the same oil for dipping. Between dips, any sediment settles to the bottom of the container.
Steve

Reynolds 

I used grease on the bearings when I disassembled the hub at about 6000kms, but probably the ATF has washed it away by now. There is a very small leakage at both sides, but I just clean it with a rag when there is some dust stuck. My bike is always on its kickstand, but it fell once and there was a puddle under the left dropout. I understand the seals are not designed for keeping oil in, but when I replace the ATF about once a year, there is still plenty of it inside.